# Problem on encoding logistic functions

ALEX PINEDA shared this problem 1 year ago
In Progress

Whenever I encode a logistic function such as f(x) = (1/(A * e^(g * x) + B)), where the variables A, B and g are parameters, my GeoGebra App or even its Graphing Calculator crashes once I adjust the parameters of the function. It happens in my iPhone SE operating iOS 13.7. Both GeoGebra App and Its Graphing Calculator I am currently using are updated as 5.0.604. I have an attached video of a problem I am concerning. I hope for a quick and positive response. Thank you for considering my message.

Alex

GeoGebra User

1

The video would be very helpful thanks - would you be able to email it to support@geogebra.org as it hasn't uploaded here?

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I send the video to the email you mention. Sorry I thought I successfully uploaded the video in my message.

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Sorry, we're having trouble reproducing this one. Does it crash dragging any slider or just "g"?

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Currently, my main GeoGebra still crashes whichever variables I slide. I tried to encode other functions related to logistic functions but still crashed when I slided each variable.

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Here are the functions I tried to encode and the get crashed when I slided any variable:

f(x) = (1/(A * e^(g * x) + e^B))

f(x) = (1/(e^(ln(A) * g * x) + B))

f(x) = (A/(e^(g * x) + B))

f(x) = (1/(A^(g * x) + B))

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• I write correctly the formula..?

• I have enough free space on my iPhone..?

• I switch off the iPhone and restart it (perhaps "the" solution...)

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As well as Jumera's excellent suggestions, please also test if you have the same problem in the GeoGebra Calculator Suite app

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Tested on iPhone SE, iOS 14 -> no problems

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I tried Jumera’s Suggestions, and here are my results:

I encode the function

f(x)=(1/(A*e^(g*x)+B))

Without white spaces

Still, It did not work.

I checked my phone storage, and I have still plenty of free storage (estimated 90GB of free space)

I restarted my phone and then tried to encode. Still, it did not work.

In a recent past, I reinstall the GeoGebra app and the Graphing Calculator. The GeoGebra still got crashed when I dragged any slider. But the Graphing Calculator did not crashed whenever I dragged any slider.

So now, while I cannot use the GeoGebra to encode any logistic functions because it crashes, fortunately, I can still encode those functions to the Graphing Calculator because it works well.

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"I can still encode those functions to the Graphing Calculator because it works well"

I don't understand : you said in your first post that it doesn't work with Graphing Calculator

and now you say it works

?

When you say "my GeoGebra app", which app is it ? Suite app ? it doesn't work with GeoGebra Suite ?

So delete now and reinstall this app (and tell us...)

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For clarification:

“GeoGebra” and “Graphing Calculator” got crashed when I dragged any variable/parameter(slider) after encoding the logistic function. I sent an email to the helpdesk to resolve my problem. Then, the helpdesk suggested me to delete the Apps and then install them again. When I tried to “GeoGebra”, it still got crashed. But when I tried “Graphing Calculator”, it worked without any problems.

I had done reinstalling the two apps before Jumera’s suggestions came.

So now, while I cannot encode any logistic function to “GeoGebra”, I can now encode any logistic function to “Graphing Calculator” or “Geometry” that I recently checked.

Forgive my underwhelming writing in my earlier posts.

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Thanks, we can see the problem now - will be fixed soon!

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ok that's clear now (there are 7 GeoGebra app... "my GeoGebra app" was GeoGebra Calculator Suite)

ok with GeoGebra Graphing Calculator, but same bug with GeoGebra Calculator Suite...